draft-gandhi-spring-stamp-srpm-06.txt   draft-gandhi-spring-stamp-srpm-07.txt 
SPRING Working Group R. Gandhi, Ed. SPRING Working Group R. Gandhi, Ed.
Internet-Draft C. Filsfils Internet-Draft C. Filsfils
Intended status: Informational Cisco Systems, Inc. Intended status: Standards Track Cisco Systems, Inc.
Expires: October 31, 2021 D. Voyer Expires: January 7, 2022 D. Voyer
Bell Canada Bell Canada
M. Chen M. Chen
Huawei Huawei
B. Janssens B. Janssens
Colt Colt
R. Foote R. Foote
Nokia Nokia
April 29, 2021 July 06, 2021
Performance Measurement Using Simple TWAMP (STAMP) for Segment Routing Performance Measurement Using Simple TWAMP (STAMP) for Segment Routing
Networks Networks
draft-gandhi-spring-stamp-srpm-06 draft-gandhi-spring-stamp-srpm-07
Abstract Abstract
Segment Routing (SR) leverages the source routing paradigm. SR is Segment Routing (SR) leverages the source routing paradigm. SR is
applicable to both Multiprotocol Label Switching (SR-MPLS) and IPv6 applicable to both Multiprotocol Label Switching (SR-MPLS) and IPv6
(SRv6) data planes. This document describes procedures for (SRv6) data planes. This document describes procedures for
Performance Measurement in SR networks using the mechanisms defined Performance Measurement in SR networks using the mechanisms defined
in RFC 8762 (Simple Two-Way Active Measurement Protocol (STAMP)) and in RFC 8762 (Simple Two-Way Active Measurement Protocol (STAMP)) and
its optional extensions defined in RFC 8972 and further augmented in its optional extensions defined in RFC 8972 and further augmented in
draft-gandhi-ippm-stamp-srpm. The procedure described is applicable draft-ietf-ippm-stamp-srpm. The procedure described is applicable to
to SR-MPLS and SRv6 data planes and is used for both links and end- SR-MPLS and SRv6 data planes and is used for both links and end-to-
to-end SR paths including SR Policies. end SR paths including SR Policies.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/. Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on October 31, 2021. This Internet-Draft will expire on January 7, 2022.
Copyright Notice Copyright Notice
Copyright (c) 2021 IETF Trust and the persons identified as the Copyright (c) 2021 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions Used in This Document . . . . . . . . . . . . . . 3 2. Conventions Used in This Document . . . . . . . . . . . . . . 3
2.1. Abbreviations . . . . . . . . . . . . . . . . . . . . . . 3 2.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
2.2. Reference Topology . . . . . . . . . . . . . . . . . . . 4 2.2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . 3
2.3. Reference Topology . . . . . . . . . . . . . . . . . . . 4
3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.1. Example STAMP Reference Model . . . . . . . . . . . . . . 6 3.1. Example STAMP Reference Model . . . . . . . . . . . . . . 6
4. Delay Measurement for Links and SR Paths . . . . . . . . . . 7 4. Delay Measurement for Links and SR Paths . . . . . . . . . . 7
4.1. Session-Sender Test Packet . . . . . . . . . . . . . . . 7 4.1. Session-Sender Test Packet . . . . . . . . . . . . . . . 7
4.1.1. Session-Sender Test Packet for Links . . . . . . . . 7 4.1.1. Session-Sender Test Packet for Links . . . . . . . . 8
4.1.2. Session-Sender Test Packet for SR Paths . . . . . . . 8 4.1.2. Session-Sender Test Packet for SR Paths . . . . . . . 8
4.2. Session-Reflector Test Packet . . . . . . . . . . . . . . 10 4.2. Session-Reflector Test Packet . . . . . . . . . . . . . . 10
4.2.1. One-way Measurement Mode . . . . . . . . . . . . . . 11 4.2.1. One-way Measurement Mode . . . . . . . . . . . . . . 11
4.2.2. Two-way Measurement Mode . . . . . . . . . . . . . . 11 4.2.2. Two-way Measurement Mode . . . . . . . . . . . . . . 11
4.2.3. Loopback Measurement Mode . . . . . . . . . . . . . . 13 4.2.3. Loopback Measurement Mode . . . . . . . . . . . . . . 13
4.3. Delay Measurement for P2MP SR Policies . . . . . . . . . 14 4.3. Delay Measurement for P2MP SR Policies . . . . . . . . . 14
4.4. Additional STAMP Test Packet Processing Rules . . . . . . 15 4.4. Additional STAMP Test Packet Processing Rules . . . . . . 15
4.4.1. TTL . . . . . . . . . . . . . . . . . . . . . . . . . 15 4.4.1. TTL . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.4.2. IPv6 Hop Limit . . . . . . . . . . . . . . . . . . . 16 4.4.2. IPv6 Hop Limit . . . . . . . . . . . . . . . . . . . 16
4.4.3. Router Alert Option . . . . . . . . . . . . . . . . . 16 4.4.3. Router Alert Option . . . . . . . . . . . . . . . . . 16
4.4.4. UDP Checksum . . . . . . . . . . . . . . . . . . . . 16 4.4.4. UDP Checksum . . . . . . . . . . . . . . . . . . . . 16
5. Packet Loss Measurement for Links and SR Paths . . . . . . . 16 5. Packet Loss Measurement for Links and SR Paths . . . . . . . 16
6. Direct Measurement for Links and SR Paths . . . . . . . . . . 16 6. Direct Measurement for Links and SR Paths . . . . . . . . . . 16
7. Session State for Links and SR Paths . . . . . . . . . . . . 17 7. Session State for Links and SR Paths . . . . . . . . . . . . 17
8. ECMP Support for SR Policies . . . . . . . . . . . . . . . . 17 8. ECMP Support for SR Policies . . . . . . . . . . . . . . . . 17
9. Security Considerations . . . . . . . . . . . . . . . . . . . 18 9. Security Considerations . . . . . . . . . . . . . . . . . . . 18
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 19
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 19 11. References . . . . . . . . . . . . . . . . . . . . . . . . . 19
11.1. Normative References . . . . . . . . . . . . . . . . . . 19 11.1. Normative References . . . . . . . . . . . . . . . . . . 19
11.2. Informative References . . . . . . . . . . . . . . . . . 19 11.2. Informative References . . . . . . . . . . . . . . . . . 19
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 22 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 22
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 22 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 22
1. Introduction 1. Introduction
Segment Routing (SR) leverages the source routing paradigm and Segment Routing (SR) leverages the source routing paradigm and
greatly simplifies network operations for Software Defined Networks greatly simplifies network operations for Software Defined Networks
skipping to change at page 3, line 23 skipping to change at page 3, line 24
Policies as defined in [I-D.ietf-spring-segment-routing-policy] are Policies as defined in [I-D.ietf-spring-segment-routing-policy] are
used to steer traffic through a specific, user-defined paths using a used to steer traffic through a specific, user-defined paths using a
stack of Segments. Built-in SR Performance Measurement (PM) is one stack of Segments. Built-in SR Performance Measurement (PM) is one
of the essential requirements to provide Service Level Agreements of the essential requirements to provide Service Level Agreements
(SLAs). (SLAs).
The Simple Two-way Active Measurement Protocol (STAMP) provides The Simple Two-way Active Measurement Protocol (STAMP) provides
capabilities for the measurement of various performance metrics in IP capabilities for the measurement of various performance metrics in IP
networks [RFC8762] without the use of a control channel to pre-signal networks [RFC8762] without the use of a control channel to pre-signal
session parameters. [RFC8972] defines optional extensions for STAMP. session parameters. [RFC8972] defines optional extensions for STAMP.
[I-D.gandhi-ippm-stamp-srpm] augments that framework to define STAMP [I-D.ietf-ippm-stamp-srpm] augments that framework to define STAMP
extensions for SR networks. extensions for SR networks.
This document describes procedures for Performance Measurement in SR This document describes procedures for Performance Measurement in SR
networks using the mechanisms defined in STAMP [RFC8762] and its networks using the mechanisms defined in STAMP [RFC8762] and its
optional extensions defined in [RFC8972] and further augmented in optional extensions defined in [RFC8972] and further augmented in
[I-D.gandhi-ippm-stamp-srpm]. The procedure described is applicable [I-D.ietf-ippm-stamp-srpm]. The procedure described is applicable to
to SR-MPLS and SRv6 data planes and is used for both links and end- SR-MPLS and SRv6 data planes and is used for both links and end-to-
to-end SR paths including SR Policies [RFC8402]. end SR paths including SR Policies [RFC8402].
2. Conventions Used in This Document 2. Conventions Used in This Document
2.1. Abbreviations 2.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119] [RFC8174]
when, and only when, they appear in all capitals, as shown here.
2.2. Abbreviations
BSID: Binding Segment ID. BSID: Binding Segment ID.
DM: Delay Measurement. DM: Delay Measurement.
ECMP: Equal Cost Multi-Path. ECMP: Equal Cost Multi-Path.
HL: Hop Limit.
HMAC: Hashed Message Authentication Code. HMAC: Hashed Message Authentication Code.
LM: Loss Measurement. LM: Loss Measurement.
MPLS: Multiprotocol Label Switching. MPLS: Multiprotocol Label Switching.
NTP: Network Time Protocol. NTP: Network Time Protocol.
OWAMP: One-Way Active Measurement Protocol. OWAMP: One-Way Active Measurement Protocol.
skipping to change at page 4, line 33 skipping to change at page 4, line 43
SRv6: Segment Routing with IPv6 data plane. SRv6: Segment Routing with IPv6 data plane.
SSID: STAMP Session Identifier. SSID: STAMP Session Identifier.
STAMP: Simple Two-way Active Measurement Protocol. STAMP: Simple Two-way Active Measurement Protocol.
TC: Traffic Class. TC: Traffic Class.
TTL: Time To Live. TTL: Time To Live.
2.2. Reference Topology 2.3. Reference Topology
In the Reference Topology shown below, the STAMP Session-Sender R1 In the Reference Topology shown below, the STAMP Session-Sender R1
initiates a STAMP test packet and the STAMP Session-Reflector R3 initiates a STAMP test packet and the STAMP Session-Reflector R3
transmits a reply test packet. The reply test packet may be transmits a reply test packet. The reply test packet may be
transmitted to the STAMP Session-Sender R1 on the same path (same set transmitted to the STAMP Session-Sender R1 on the same path (same set
of links and nodes) or a different path in the reverse direction from of links and nodes) or a different path in the reverse direction from
the path taken towards the Session-Reflector. the path taken towards the Session-Reflector.
The nodes R1 and R3 may be connected via a link or an SR path The nodes R1 and R3 may be connected via a link or an SR path
[RFC8402]. The link may be a physical interface, virtual link, or [RFC8402]. The link may be a physical interface, virtual link, or
skipping to change at page 5, line 23 skipping to change at page 5, line 30
T4 T3 T4 T3
STAMP Session-Sender STAMP Session-Reflector STAMP Session-Sender STAMP Session-Reflector
Reference Topology Reference Topology
3. Overview 3. Overview
For performance measurement in SR networks, the STAMP Session-Sender For performance measurement in SR networks, the STAMP Session-Sender
and Session-Reflector test packets defined in [RFC8762] are used. and Session-Reflector test packets defined in [RFC8762] are used.
They are used in one-way, two-way (i.e. round-trip) and loopback The STAMP test packets require to be encapsulated to be transmitted
measurement modes. Note that one-way and round-trip are referred to on a desired path under measurement. The base STAMP test packets can
in [RFC8762] and are further described in this document because of be encapsulated using IP/UDP header and may use Destination UDP port
the introduction of loopback measurement mode in SR networks. The 862 [RFC8762]. In this document, the STAMP packets using IP/UDP
procedures defined in this document are also used to infer packet header are considered for SR networks.
loss in SR networks.
The STAMP test packets are used in one-way, two-way (i.e. round-trip)
and loopback measurement modes. Note that one-way and round-trip are
referred to in [RFC8762] and are further described in this document
because of the introduction of loopback measurement mode in SR
networks. The procedures defined in this document are also used to
infer packet loss in SR networks.
The STAMP test packets are transmitted on the same path as the data The STAMP test packets are transmitted on the same path as the data
traffic flow under measurement to measure the delay and packet loss traffic flow under measurement to measure the delay and packet loss
experienced by the data traffic flow. experienced by the data traffic flow.
Typically, the STAMP test packets are transmitted along an IP path Typically, the STAMP test packets are transmitted along an IP path
between a Session-Sender and a Session-Reflector to measure delay and between a Session-Sender and a Session-Reflector to measure delay and
packet loss along that IP path. Matching the forward and reverse packet loss along that IP path. Matching the forward and reverse
direction paths for STAMP test packets, even for directly connected direction paths for STAMP test packets, even for directly connected
nodes is not guaranteed. nodes is not guaranteed.
It may be desired in SR networks that the same path (same set of It may be desired in SR networks that the same path (same set of
links and nodes) between the Session-Sender and Session-Reflector be links and nodes) between the Session-Sender and Session-Reflector be
used for the STAMP test packets in both directions. This is achieved used for the STAMP test packets in both directions. This is achieved
by using the optional STAMP extensions for SR-MPLS and SRv6 networks by using the optional STAMP extensions for SR-MPLS and SRv6 networks
specified in [I-D.gandhi-ippm-stamp-srpm]. The STAMP Session- specified in [I-D.ietf-ippm-stamp-srpm]. The STAMP Session-Reflector
Reflector uses the return path parameters for the reply test packet uses the return path parameters for the reply test packet from the
from the received STAMP test packet, as described in received STAMP test packet, as described in
[I-D.gandhi-ippm-stamp-srpm]. This way signaling and maintaining [I-D.ietf-ippm-stamp-srpm]. This way signaling and maintaining
dynamic SR network state for the STAMP sessions on the Session- dynamic SR network state for the STAMP sessions on the Session-
Reflector are avoided. Reflector are avoided.
The optional STAMP extensions defined in [RFC8972] are used for The optional STAMP extensions defined in [RFC8972] are used for
direct measurement packet loss in SR networks. direct measurement packet loss in SR networks.
3.1. Example STAMP Reference Model 3.1. Example STAMP Reference Model
An example of a STAMP reference model with some of the typical An example of a STAMP reference model with some of the typical
measurement parameters including the Reflector UDP port for STAMP measurement parameters including the Destination UDP port for STAMP
test session is shown in the following Figure 1: test session is shown in the following Figure 1:
+------------+ +------------+
| Controller | | Controller |
+------------+ +------------+
/ \ / \
Reflector UDP Port / \ Reflector UDP Port Destination UDP Port / \ Destination UDP Port
Authentication Mode / \ Authentication Mode Authentication Mode / \ Authentication Mode
Key-chain / \ Key-chain Key-chain / \ Key-chain
Timestamp Format / \ Timestamp Format Timestamp Format / \ Timestamp Format
Packet Loss Type / \ Reflector Mode Packet Loss Type / \ Session-Reflector Mode
Delay Measurement Mode / \ Delay Measurement Mode / \
v v v v
+-------+ +-------+ +-------+ +-------+
| | | | | | | |
| R1 |==========| R3 | | R1 |==========| R3 |
| | | | | | | |
+-------+ +-------+ +-------+ +-------+
STAMP Session-Sender STAMP Session-Reflector STAMP Session-Sender STAMP Session-Reflector
Figure 1: Example STAMP Reference Model Figure 1: Example STAMP Reference Model
A reflector UDP port number is selected as described in [RFC8762]. A Destination UDP port number is selected as described in [RFC8762].
The same reflector UDP port can be used for STAMP test sessions for The same Destination UDP port can be used for STAMP test sessions for
link and end-to-end SR paths. In this case, the reflector UDP port link and end-to-end SR paths. In this case, the Destination UDP port
does not distinguish between link or end-to-end SR path measurements. does not distinguish between link or end-to-end SR path measurements.
Example of the Timestamp Format is Precision Time Protocol 64-bit Example of the Timestamp Format is Precision Time Protocol 64-bit
truncated (PTPv2) [IEEE1588] and Network Time Protocol (NTP). By truncated (PTPv2) [IEEE1588] and Network Time Protocol (NTP). By
default, the Session-Reflector replies in kind to the timestamp default, the Session-Reflector replies in kind to the timestamp
format received in the received Session-Sender test packet, as format received in the received Session-Sender test packet, as
indicated by the "Z" field in the Error Estimate field as described indicated by the "Z" field in the Error Estimate field as described
in [RFC8762]. in [RFC8762].
The Session-Reflector mode can be Stateful or Stateless as defined in The Session-Reflector mode can be Stateful or Stateless as defined in
skipping to change at page 7, line 36 skipping to change at page 8, line 14
+---------------------------------------------------------------+ +---------------------------------------------------------------+
| IP Header | | IP Header |
. Source IP Address = Session-Sender IPv4 or IPv6 Address . . Source IP Address = Session-Sender IPv4 or IPv6 Address .
. Destination IP Address=Session-Reflector IPv4 or IPv6 Address. . Destination IP Address=Session-Reflector IPv4 or IPv6 Address.
. Protocol = UDP . . Protocol = UDP .
. . . .
+---------------------------------------------------------------+ +---------------------------------------------------------------+
| UDP Header | | UDP Header |
. Source Port = As chosen by Session-Sender . . Source Port = As chosen by Session-Sender .
. Destination Port = User-configured Reflector Port | 862 . . Destination Port = User-configured Destination Port | 862 .
. . . .
+---------------------------------------------------------------+ +---------------------------------------------------------------+
| Payload = Test Packet as specified in Section 4.2 of RFC 8762 | | Payload = Test Packet as specified in Section 3 of RFC 8972 |
. in Figure 1 and Figure 3 .
. . . .
+---------------------------------------------------------------+ +---------------------------------------------------------------+
Figure 2: Example Session-Sender Test Packet Figure 2: Example Session-Sender Test Packet
4.1.1. Session-Sender Test Packet for Links 4.1.1. Session-Sender Test Packet for Links
The STAMP Session-Sender test packet as shown in Figure 2 is The STAMP Session-Sender test packet as shown in Figure 2 is
transmitted over the link under delay measurement. The local and transmitted over the link under delay measurement. The local and
remote IP addresses of the link are used as Source and Destination remote IP addresses of the link are used as Source and Destination
Addresses, respectively. For IPv6 links, the link local addresses Addresses, respectively. For IPv6 links, the link local addresses
[RFC7404] can be used in the IPv6 header. The Session-Sender may use [RFC7404] can be used in the IPv6 header. The Session-Sender may use
the local Address Resolution Protocol (ARP) table, Neighbor the local Address Resolution Protocol (ARP) table, Neighbor
Solicitation or other bootstrap method to find the IP address for the Solicitation or other bootstrap method to find the IP address for the
links and refresh. An IPv4 address from the range 127/8 or IPv6 links and refresh. SR encapsulation (e.g. adjacency SID of the link)
loopback address ::1/128 [RFC4291] must not be used to IP route test can be added for transmitting the STAMP test packets for links.
packets in a network.
4.1.2. Session-Sender Test Packet for SR Paths 4.1.2. Session-Sender Test Packet for SR Paths
The delay measurement for end-to-end SR path in an SR network is The delay measurement for end-to-end SR path in an SR network is
applicable to both end-to-end SR-MPLS and SRv6 paths including SR applicable to both end-to-end SR-MPLS and SRv6 paths including SR
Policies. Policies.
The STAMP Session-Sender IPv4 or IPv6 address is used as the Source The STAMP Session-Sender (the head-end of the SR Policy) IPv4 or IPv6
Address. The SR Policy endpoint IPv4 or IPv6 address is used as the address MUST be used as the Source Address in the IP header of the
Destination Address. test packet. The STAMP Session-Reflector (the SR Policy endpoint)
IPv4 or IPv6 address MUST be used as the Destination Address in the
IP header of the test packet.
In the case of Color-Only Destination Steering, with IPv4 endpoint of In the case of Color-Only Destination Steering, with IPv4 endpoint of
0.0.0.0 or IPv6 endpoint of ::0 0.0.0.0 or IPv6 endpoint of ::0
[I-D.ietf-spring-segment-routing-policy], the loopback address from [I-D.ietf-spring-segment-routing-policy], the loopback address from
the range 127/8 for IPv4, or the loopback address ::1/128 for IPv6 the range 127/8 for IPv4, or the loopback address ::1/128 for IPv6
[RFC4291] is used as the Session-Reflector Address, respectively. [RFC4291] is used as the Session-Reflector Address, respectively.
4.1.2.1. Session-Sender Test Packet for SR-MPLS Policies 4.1.2.1. Session-Sender Test Packet for SR-MPLS Policies
An SR-MPLS Policy may contain a number of Segment Lists (SLs). A An SR-MPLS Policy may contain a number of Segment Lists (SLs). A
STAMP Session-Sender test packet is transmitted for each Segment List STAMP Session-Sender test packet MUST be transmitted for each Segment
of the SR-MPLS Policy. The content of an example STAMP Session- List of the SR-MPLS Policy. The content of an example STAMP Session-
Sender test packet for an end-to-end SR-MPLS Policy is shown in Sender test packet for an end-to-end SR-MPLS Policy is shown in
Figure 3. Figure 3.
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Segment(1) | TC |S| TTL | | Segment(1) | TC |S| TTL |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
. . . .
. . . .
skipping to change at page 9, line 17 skipping to change at page 9, line 44
The Path Segment Identifier (PSID) The Path Segment Identifier (PSID)
[I-D.ietf-spring-mpls-path-segment] of an SR-MPLS Policy can be [I-D.ietf-spring-mpls-path-segment] of an SR-MPLS Policy can be
carried in the MPLS header as shown in Figure 3, and can be used for carried in the MPLS header as shown in Figure 3, and can be used for
direct measurement as described in Section 6, titled "Direct direct measurement as described in Section 6, titled "Direct
Measurement for Links and SR Paths". Measurement for Links and SR Paths".
4.1.2.2. Session-Sender Test Packet for SRv6 Policies 4.1.2.2. Session-Sender Test Packet for SRv6 Policies
An SRv6 Policy may contain a number of Segment Lists. A STAMP An SRv6 Policy may contain a number of Segment Lists. A STAMP
Session-Sender test packet is transmitted for each Segment List of Session-Sender test packet MUST be transmitted for each Segment List
the SRv6 Policy. An SRv6 Policy can contain an SRv6 Segment Routing of the SRv6 Policy. An SRv6 Policy can contain an SRv6 Segment
Header (SRH) carrying a Segment List as described in [RFC8754]. The Routing Header (SRH) carrying a Segment List as described in
content of an example STAMP Session-Sender test packet for an end-to- [RFC8754]. The content of an example STAMP Session-Sender test
end SRv6 Policy is shown in Figure 4. packet for an end-to-end SRv6 Policy is shown in Figure 4.
The SRv6 network programming is described in [RFC8986]. The The SRv6 network programming is described in [RFC8986]. The
procedure defined for Upper-Layer Header processing for SRv6 End SIDs procedure defined for Upper-Layer Header processing for SRv6 End SIDs
in Section 4.1.1 in [RFC8986] is used to process the IPv6/UDP header in Section 4.1.1 in [RFC8986] is used to process the IPv6/UDP header
in the received test packets on the Session-Reflector. in the received test packets on the Session-Reflector.
+---------------------------------------------------------------+ +---------------------------------------------------------------+
| IP Header | | IP Header |
. Source IP Address = Session-Sender IPv6 Address . . Source IP Address = Session-Sender IPv6 Address .
. Destination IP Address = Destination IPv6 Address . . Destination IP Address = Destination IPv6 Address .
. Protocol = UDP .
. . . .
+---------------------------------------------------------------+ +---------------------------------------------------------------+
| SRH as specified in RFC 8754 | | SRH as specified in RFC 8754 |
. <PSID, Segment List> . . <PSID, Segment List> .
. . . .
+---------------------------------------------------------------+ +---------------------------------------------------------------+
| IP Header |
. Source IP Address = Session-Sender IPv6 Address .
. Destination IP Address = Session-Reflector IPv6 Address .
. Protocol = UDP .
. .
+---------------------------------------------------------------+
| UDP Header | | UDP Header |
. Source Port = As chosen by Session-Sender . . Source Port = As chosen by Session-Sender .
. Destination Port = User-configured Reflector Port | 862 . . Destination Port = User-configured Destination Port | 862 .
. . . .
+---------------------------------------------------------------+ +---------------------------------------------------------------+
| Payload = Test Packet as specified in Section 4.2 of RFC 8762 | | Payload = Test Packet as specified in Section 3 of RFC 8972 |
. in Figure 1 and Figure 3 .
. . . .
+---------------------------------------------------------------+ +---------------------------------------------------------------+
Figure 4: Example Session-Sender Test Packet for SRv6 Policy Figure 4: Example Session-Sender Test Packet for SRv6 Policy
The Segment List (SL) may be empty and no SRH may be carried. The Segment List (SL) may be empty and no SRH may be carried.
The Path Segment Identifier (PSID) The Path Segment Identifier (PSID)
[I-D.ietf-spring-srv6-path-segment] of the SRV6 Policy can be carried [I-D.ietf-spring-srv6-path-segment] of the SRV6 Policy can be carried
in the SRH as shown in Figure 4 and can be used for direct in the SRH as shown in Figure 4 and can be used for direct
skipping to change at page 11, line 18 skipping to change at page 11, line 18
. Destination IP Address . . Destination IP Address .
. = Source IP Address from Received Test Packet . . = Source IP Address from Received Test Packet .
. Protocol = UDP . . Protocol = UDP .
. . . .
+---------------------------------------------------------------+ +---------------------------------------------------------------+
| UDP Header | | UDP Header |
. Source Port = As chosen by Session-Reflector . . Source Port = As chosen by Session-Reflector .
. Destination Port = Source Port from Received Test Packet . . Destination Port = Source Port from Received Test Packet .
. . . .
+---------------------------------------------------------------+ +---------------------------------------------------------------+
| Payload = Test Packet as specified in Section 4.3 of RFC 8762 | | Payload = Test Packet as specified in Section 3 of RFC 8972 |
. in Figure 2 and Figure 4 .
. . . .
+---------------------------------------------------------------+ +---------------------------------------------------------------+
Figure 5: Example Session-Reflector Test Packet Figure 5: Example Session-Reflector Test Packet
4.2.1. One-way Measurement Mode 4.2.1. One-way Measurement Mode
In one-way delay measurement mode, a reply test packet as shown in In one-way delay measurement mode, a reply test packet as shown in
Figure 5 is transmitted by the STAMP Session-Reflector, for both Figure 5 is transmitted by the STAMP Session-Reflector, for both
links and end-to-end SR Policies. The reply test packet may be links and end-to-end SR Policies. The reply test packet may be
transmitted on the same path or a different path in the reverse transmitted on the same path or a different path in the reverse
direction. direction.
The STAMP Session-Sender address may not be reachable via IP route The STAMP Session-Sender address may not be reachable via IP route
from the STAMP Session-Reflector. The STAMP Session-Sender in this from the STAMP Session-Reflector. The STAMP Session-Sender in this
case can send its reachability path information to the STAMP Session- case MUST send its reachability path information to the STAMP
Reflector using the Return Path TLV defined in Session-Reflector using the Return Path TLV defined in
[I-D.gandhi-ippm-stamp-srpm]. [I-D.ietf-ippm-stamp-srpm].
In this mode, as per Reference Topology, all timestamps T1, T2, T3, In this mode, as per Reference Topology, all timestamps T1, T2, T3,
and T4 are collected by the test packets. However, only timestamps and T4 are collected by the test packets. However, only timestamps
T1 and T2 are used to measure one-way delay as (T2 - T1). The one- T1 and T2 are used to measure one-way delay as (T2 - T1). The one-
way delay measurement mode requires the clock on the Session-Sender way delay measurement mode requires the clock on the Session-Sender
and Session-Reflector to be synchronized. and Session-Reflector to be synchronized.
4.2.2. Two-way Measurement Mode 4.2.2. Two-way Measurement Mode
In two-way (i.e. round-trip) delay measurement mode, a reply test In two-way (i.e. round-trip) delay measurement mode, a reply test
packet as shown in Figure 5 is transmitted by the STAMP Session- packet as shown in Figure 5 is transmitted by the STAMP Session-
Reflector on the same path in the reverse direction, e.g. on the Reflector on the same path in the reverse direction, e.g. on the
reverse direction link or associated reverse SR path reverse direction link or associated reverse SR path
[I-D.ietf-pce-sr-bidir-path]. [I-D.ietf-pce-sr-bidir-path].
For two-way delay measurement mode for links, the STAMP Session- For two-way delay measurement mode for links, the STAMP Session-
Reflector needs to transmit the reply test packet on the same link Reflector transmits the reply test packet on the same link where the
where the test packet is received. The STAMP Session-Sender can test packet is received. The STAMP Session-Sender can request in the
request in the test packet to the STAMP Session-Reflector to transmit test packet to the STAMP Session-Reflector to transmit the reply test
the reply test packet back on the same link using the Control Code packet back on the same link using the Control Code Sub-TLV in the
Sub-TLV in the Return Path TLV defined in Return Path TLV defined in [I-D.ietf-ippm-stamp-srpm].
[I-D.gandhi-ippm-stamp-srpm].
For two-way delay measurement mode for end-to-end SR paths, the STAMP For two-way delay measurement mode for end-to-end SR paths, the STAMP
Session-Reflector needs to transmit the reply test packet on a Session-Reflector transmits the reply test packet on a specific
specific reverse path. The STAMP Session-Sender can request in the reverse path. The STAMP Session-Sender can request in the test
test packet to the STAMP Session-Reflector to transmit the reply test packet to the STAMP Session-Reflector to transmit the reply test
packet back on a given reverse path using a Segment List sub-TLV in packet back on a given reverse path using a Segment List sub-TLV in
the Return Path TLV defined in [I-D.gandhi-ippm-stamp-srpm]. the Return Path TLV defined in [I-D.ietf-ippm-stamp-srpm].
In this mode, as per Reference Topology, all timestamps T1, T2, T3, In this mode, as per Reference Topology, all timestamps T1, T2, T3,
and T4 are collected by the test packets. All four timestamps are and T4 are collected by the test packets. All four timestamps are
used to measure two-way delay as ((T4 - T1) - (T3 - T2)). When clock used to measure two-way delay as ((T4 - T1) - (T3 - T2)). When clock
synchronization on the Session-Sender and Session-Reflector nodes is synchronization on the Session-Sender and Session-Reflector nodes is
not possible, the one-way delay can be derived using two-way delay not possible, the one-way delay can be derived using two-way delay
divided by two. divided by two.
4.2.2.1. Session-Reflector Test Packet for SR-MPLS Policies 4.2.2.1. Session-Reflector Test Packet for SR-MPLS Policies
skipping to change at page 13, line 20 skipping to change at page 13, line 20
Policy with SRH is shown in Figure 7. Policy with SRH is shown in Figure 7.
The procedure defined for Upper-Layer Header processing for SRv6 End The procedure defined for Upper-Layer Header processing for SRv6 End
SIDs in Section 4.1.1 in [RFC8986] is used to process the IPv6/UDP SIDs in Section 4.1.1 in [RFC8986] is used to process the IPv6/UDP
header in the received reply test packets on the Session-Sender. header in the received reply test packets on the Session-Sender.
+---------------------------------------------------------------+ +---------------------------------------------------------------+
| IP Header | | IP Header |
. Source IP Address = Session-Reflector IPv6 Address . . Source IP Address = Session-Reflector IPv6 Address .
. Destination IP Address = Destination IPv6 Address . . Destination IP Address = Destination IPv6 Address .
. Protocol = UDP .
. . . .
+---------------------------------------------------------------+ +---------------------------------------------------------------+
| SRH as specified in RFC 8754 | | SRH as specified in RFC 8754 |
. <Segment List> . . <Segment List> .
. . . .
+---------------------------------------------------------------+ +---------------------------------------------------------------+
| IP Header |
. Source IP Address = Session-Reflector IPv6 Address .
. Destination IP Address .
. = Source IPv6 Address from Received Test Packet .
. Protocol = UDP .
. .
+---------------------------------------------------------------+
| UDP Header | | UDP Header |
. Source Port = As chosen by Session-Reflector . . Source Port = As chosen by Session-Reflector .
. Destination Port = Source Port from Received Test Packet . . Destination Port = Source Port from Received Test Packet .
. . . .
+---------------------------------------------------------------+ +---------------------------------------------------------------+
| Payload = Test Packet as specified in Section 4.3 of RFC 8762 | | Payload = Test Packet as specified in Section 3 of RFC 8972 |
. in Figure 2 and Figure 4 .
. . . .
+---------------------------------------------------------------+ +---------------------------------------------------------------+
Figure 7: Example Session-Reflector Test Packet for SRv6 Policy Figure 7: Example Session-Reflector Test Packet for SRv6 Policy
4.2.3. Loopback Measurement Mode 4.2.3. Loopback Measurement Mode
The STAMP Session-Sender test packets are transmitted in loopback The STAMP Session-Sender test packets are transmitted in loopback
mode to measure loopback delay of a bidirectional circular path. In mode to measure loopback delay of a bidirectional circular path. In
this mode, the received Session-Sender test packets are not punted this mode, the received Session-Sender test packets are not punted
out of the fast path in forwarding (to slow path or control-plane) at out of the fast path in forwarding (i.e. to slow path or control-
the STAMP Session-Reflector. In other words, the Session-Reflector plane) at the STAMP Session-Reflector. In other words, the Session-
does not process them and generate reply test packets. Reflector does not process them and generate Session-Reflector test
packets. This is a new measurement mode, not defined by STAMP
process [RFC8762].
The IP header of the STAMP Session-Sender test packet contains the The STAMP Session-Sender MUST set the Destination UDP port to the UDP
Destination Address equals to the STAMP Session-Sender address and port it uses to receive the reply STAMP test packets. Since the
the Source Address equals to the STAMP Session-Reflector address. Session-Reflector does not support the STAMP process, the loopback
The Session-Sender sets the Reflector UDP port that it uses to function simply makes the necessary changes to the encapsulation
receive the test packet. Optionally, the STAMP Session-Sender test including IP and UDP headers to return the test packet to the
packet can carry the return path information (e.g. return path label Session-Sender. The typical Session-Reflector test packet is not
stack for SR-MPLS) as part of the SR header. used in this mode. The loopback function simply returns the received
Session-Sender test packet to the Session-Sender without STAMP
modifications defined in [RFC8762].
The Session-Sender can use the SSID field in the reply test packet In case of SR-MPLS paths, the SR-MPLS header can contain the MPLS
and/ or local configuration to know that the test session is using label stack of the forward path or both forward and the reverse
the loopback mode. As the reply test packet is not generated by the paths. The IP header of the STAMP Session-Sender test packets MUST
STAMP Session-Reflector, the STAMP Session-Sender ignores the set the Destination Address equal to the STAMP Session-Sender address
'Session-Sender Sequence Number', 'Session-Sender Timestamp', and the Source Address equal to the STAMP Session-Reflector address.
'Session-Sender Error Estimate', and 'Session-Sender TTL' in the
received test packet. The Session-Sender sets these fields to 0 upon
transmission.
In this mode, as per Reference Topology, the timestamps T1 and T4 are In case of SRv6 paths, the SRH can contain the Segment List of the
collected by the test packets. Both these timestamps are used to forward path or both forward and the reverse paths. In the former
measure loopback delay as (T4 - T1). When STAMP capability on the case, an inner IPv6 header (after SRH and before UDP header) MUST be
Session-Reflector node is not possible, the one-way delay can be added that contains the Destination Address equal to the STAMP
derived using loopback delay divided by two. In this mode, the Session-Sender address and the Source Address equal to the STAMP
responder node processing time component reflects only the time Session-Reflector address.
required to loop the test packet from the incoming interface to the
outgoing interface in forwarding plane. The Session-Sender may use the SSID field in the received reply test
packet or local configuration to identify its test session using the
loopback mode. In the received Session-Sender test packet at the
Session-Sender, the 'Session-Sender Sequence Number', 'Session-Sender
Timestamp', 'Session-Sender Error Estimate', and 'Session-Sender TTL'
fields are not present in this mode.
In this mode, as per Reference Topology, the test packet received
back at the Session-Sender retrieves the timestamp T1 from the test
packet and adds the received timestamp T4 locally. Both these
timestamps are used to measure the loopback delay as (T4 - T1). The
one-way delay can be derived using the loopback delay divided by two.
In loopback mode, the loopback delay includes the processing delay on
the Session-Reflector. The Session-Reflector processing delay
component includes only the time required to loop the test packet
from the incoming interface to the outgoing interface in forwarding
plane.
4.3. Delay Measurement for P2MP SR Policies 4.3. Delay Measurement for P2MP SR Policies
The Point-to-Multipoint (P2MP) SR path that originates from a root The Point-to-Multipoint (P2MP) SR path that originates from a root
node terminates on multiple destinations called leaf nodes (e.g. node terminates on multiple destinations called leaf nodes (e.g.
P2MP SR Policy [I-D.ietf-pim-sr-p2mp-policy]). P2MP SR Policy [I-D.ietf-pim-sr-p2mp-policy]).
The procedures for delay and loss measurement described in this The procedures for delay and loss measurement described in this
document for end-to-end P2P SR Policies are also equally applicable document for end-to-end P2P SR Policies are also equally applicable
to the P2MP SR Policies. The procedure for one-way measurement is to the P2MP SR Policies. The procedure for one-way measurement is
defined as following: defined as following:
o The STAMP Session-Sender root node transmits test packets using o The STAMP Session-Sender root node transmits test packets using
the Tree-SID defined in [I-D.ietf-pim-sr-p2mp-policy] for the P2MP the Tree-SID defined in [I-D.ietf-pim-sr-p2mp-policy] for the P2MP
SR-MPLS Policy as shown in Figure 8. The STAMP Session-Sender SR-MPLS Policy as shown in Figure 8. The STAMP Session-Sender
test packets may contain the replication SID as defined in test packets may contain the replication SID as defined in
[I-D.ietf-spring-sr-replication-segment]. [I-D.ietf-spring-sr-replication-segment].
o The Destination Address is set to the loopback address from the o The Destination Address MUST be set to the loopback address from
range 127/8 for IPv4, or the loopback address ::1/128 for IPv6. the range 127/8 for IPv4, or the loopback address ::1/128 for
IPv6.
o Each STAMP Session-Reflector leaf node transmits its node address
in the Source Address of the reply test packets shown in Figure 5.
This allows the STAMP Session-Sender root node to identify the o Each STAMP Session-Reflector leaf node MUST transmit its node
STAMP Session-Reflector leaf nodes of the P2MP SR Policy. address in the Source Address of the reply test packets shown in
Figure 5. This allows the STAMP Session-Sender root node to
identify the STAMP Session-Reflector leaf nodes of the P2MP SR
Policy.
o The P2MP root node measures the delay for each P2MP leaf node o The P2MP root node measures the delay for each P2MP leaf node
individually. individually.
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Tree-SID | TC |S| TTL | | Tree-SID | TC |S| TTL |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
. . . .
skipping to change at page 15, line 40 skipping to change at page 16, line 8
4.4. Additional STAMP Test Packet Processing Rules 4.4. Additional STAMP Test Packet Processing Rules
The processing rules described in this section are applicable to the The processing rules described in this section are applicable to the
STAMP test packets for links and end-to-end SR paths including SR STAMP test packets for links and end-to-end SR paths including SR
Policies. Policies.
4.4.1. TTL 4.4.1. TTL
The TTL field in the IPv4 and MPLS headers of the STAMP Session- The TTL field in the IPv4 and MPLS headers of the STAMP Session-
Sender and STAMP Session-Reflector test packets is set to 255, except Sender and STAMP Session-Reflector test packet is set to 255 as per
in the following cases. Generalized TTL Security Mechanism (GTSM) [RFC5082].
When using the Session-Reflector IPv4 Address from the range 127/8,
the TTL field in the IPv4 header is set to 1, for otherwise,
encapsulated packets.
For link delay, the TTL field in the STAMP test packet is set to 1 in
one-way and two-way delay measurement modes.
4.4.2. IPv6 Hop Limit 4.4.2. IPv6 Hop Limit
The Hop Limit field in the IPv6 and SRH headers of the STAMP Session- The Hop Limit (HL) field in the IPv6 and SRH headers of the STAMP
Sender and STAMP Session-Reflector test packets is set to 255, except Session-Sender and STAMP Session-Reflector test packet is set to 255
in the following cases. as per Generalized TTL Security Mechanism (GTSM) [RFC5082].
When using the Session-Reflector IPv6 Address of loopback address
::1/128, the Hop Limit field in the IPv6 header is set to 1, for
otherwise, encapsulated packets.
For link delay, the Hop Limit field in the STAMP test packet is set
to 1 in one-way and two-way delay measurement modes.
4.4.3. Router Alert Option 4.4.3. Router Alert Option
The Router Alert IP option (RAO) [RFC2113] is not set in the STAMP The Router Alert IP option (RAO) [RFC2113] is not set in the STAMP
test packets for links and end-to-end SR paths. test packets for links and end-to-end SR paths.
4.4.4. UDP Checksum 4.4.4. UDP Checksum
For IPv4 test packets, where the hardware is not capable of re- For IPv4 test packets, where the hardware is not capable of re-
computing the UDP checksum or adding checksum complement [RFC7820], computing the UDP checksum or adding checksum complement [RFC7820],
skipping to change at page 16, line 42 skipping to change at page 16, line 41
defined in [RFC6936] for the UDP checksum. defined in [RFC6936] for the UDP checksum.
5. Packet Loss Measurement for Links and SR Paths 5. Packet Loss Measurement for Links and SR Paths
The procedure described in Section 4 for delay measurement using The procedure described in Section 4 for delay measurement using
STAMP test packets can be used to detect (test) packet loss for links STAMP test packets can be used to detect (test) packet loss for links
and end-to-end SR paths. The Sequence Number field in the STAMP test and end-to-end SR paths. The Sequence Number field in the STAMP test
packet is used as described in Section 4 "Theory of Operation" where packet is used as described in Section 4 "Theory of Operation" where
Stateful and Stateless Session-Reflector operations are defined Stateful and Stateless Session-Reflector operations are defined
[RFC8762], to detect round-trip, near-end (forward) and far-end [RFC8762], to detect round-trip, near-end (forward) and far-end
(backward) packet loss. (backward) packet loss. In the case of the loopback mode introduced
in this document, only the round-trip packet loss is applicable.
This method can be used for inferred packet loss measurement, This method can be used for inferred packet loss measurement,
however, it does not provide accurate data packet loss metric. however, it provides only approximate view of the data packet loss.
6. Direct Measurement for Links and SR Paths 6. Direct Measurement for Links and SR Paths
The STAMP "Direct Measurement" TLV (Type 5) defined in [RFC8972] can The STAMP "Direct Measurement" TLV (Type 5) defined in [RFC8972] can
be used in SR networks for data packet loss measurement. The STAMP be used in SR networks for data packet loss measurement. The STAMP
test packets with this TLV are transmitted using the procedures test packets with this TLV are transmitted using the procedures
described in Section 4 to collect the transmit and receive counters described in Section 4 to collect the transmit and receive counters
of the data flow for the links and end-to-end SR paths. of the data flow for the links and end-to-end SR paths.
The PSID carried in the received data packet for the traffic flow The PSID carried in the received data packet for the traffic flow
skipping to change at page 17, line 40 skipping to change at page 17, line 40
The STAMP test session state is declared idle (or failed) when The STAMP test session state is declared idle (or failed) when
consecutive N number of reply test packets are not received at the consecutive N number of reply test packets are not received at the
STAMP Session-Sender, where N is locally provisioned value. STAMP Session-Sender, where N is locally provisioned value.
8. ECMP Support for SR Policies 8. ECMP Support for SR Policies
An SR Policy can have ECMPs between the source and transit nodes, An SR Policy can have ECMPs between the source and transit nodes,
between transit nodes and between transit and destination nodes. between transit nodes and between transit and destination nodes.
Usage of Anycast SID [RFC8402] by an SR Policy can result in ECMP Usage of Anycast SID [RFC8402] by an SR Policy can result in ECMP
paths via transit nodes part of that Anycast group. The test packets paths via transit nodes part of that Anycast group. The test packets
need to be transmitted to traverse different ECMP paths to measure SHOULD be transmitted to traverse different ECMP paths to measure
end-to-end delay of an SR Policy. end-to-end delay of an SR Policy.
Forwarding plane has various hashing functions available to forward Forwarding plane has various hashing functions available to forward
packets on specific ECMP paths. The mechanisms described in packets on specific ECMP paths. The mechanisms described in
[RFC8029] and [RFC5884] for handling ECMPs are also applicable to the [RFC8029] and [RFC5884] for handling ECMPs are also applicable to the
delay measurement. delay measurement.
For SR-MPLS Policy, sweeping of MPLS entropy label [RFC6790] values
can be used in Session-Sender test packets and Session-Reflector test
packets to take advantage of the hashing function in forwarding plane
to influence the ECMP path taken by them.
In IPv4 header of the STAMP Session-Sender test packets, sweeping of In IPv4 header of the STAMP Session-Sender test packets, sweeping of
Session-Reflector Address from the range 127/8 can be used to Session-Reflector Address from the range 127/8 can be used to
exercise ECMP paths. In this case, both the forward and the return exercise ECMP paths. In this case, both the forward and the return
paths must be SR-MPLS paths when using the loopback mode. paths MUST be SR-MPLS paths when using the loopback mode.
As specified in [RFC6437], Flow Label field in the outer IPv6 header As specified in [RFC6437], Flow Label field in the outer IPv6 header
can also be used for sweeping to exercise different IPv6 ECMP paths. can also be used for sweeping to exercise different IPv6 ECMP paths.
The "Destination Node Address" TLV [I-D.gandhi-ippm-stamp-srpm] can The "Destination Node Address" TLV [I-D.ietf-ippm-stamp-srpm] MUST be
be carried in the STAMP Session-Sender test packet to identify the carried in the STAMP Session-Sender test packet to identify the
intended Session-Reflector, for example, in case of using IPv4 intended Session-Reflector, when using IPv4 Session-Reflector Address
Session-Reflector Address from 127/8 range when the STAMP test packet from 127/8 range for a P2P SR Policy, when the STAMP test packet is
is encapsulated by a tunneling protocol or an MPLS Segment list. The encapsulated by a tunneling protocol or an MPLS Segment List.
STAMP Session-Reflector must not transmit reply test packet if it is
not the intended destination node in the "Destination Node Address"
TLV [I-D.gandhi-ippm-stamp-srpm].
9. Security Considerations 9. Security Considerations
The performance measurement is intended for deployment in well- The performance measurement is intended for deployment in well-
managed private and service provider networks. As such, it assumes managed private and service provider networks. As such, it assumes
that a node involved in a measurement operation has previously that a node involved in a measurement operation has previously
verified the integrity of the path and the identity of the far-end verified the integrity of the path and the identity of the far-end
STAMP Session-Reflector. STAMP Session-Reflector.
If desired, attacks can be mitigated by performing basic validation If desired, attacks can be mitigated by performing basic validation
skipping to change at page 18, line 42 skipping to change at page 18, line 44
Use of HMAC-SHA-256 in the authenticated mode protects the data Use of HMAC-SHA-256 in the authenticated mode protects the data
integrity of the test packets. SRv6 has HMAC protection integrity of the test packets. SRv6 has HMAC protection
authentication defined for SRH [RFC8754]. Hence, test packets for authentication defined for SRH [RFC8754]. Hence, test packets for
SRv6 may not need authentication mode. Cryptographic measures may be SRv6 may not need authentication mode. Cryptographic measures may be
enhanced by the correct configuration of access-control lists and enhanced by the correct configuration of access-control lists and
firewalls. firewalls.
The security considerations specified in [RFC8762] and [RFC8972] also The security considerations specified in [RFC8762] and [RFC8972] also
apply to the procedures described in this document. apply to the procedures described in this document.
The Security Considerations specified in [I-D.ietf-ippm-stamp-srpm]
are also equally applicable to the procedures defined in this
document.
When using the procedures defined in [RFC6936], the security When using the procedures defined in [RFC6936], the security
considerations specified in [RFC6936] also apply. considerations specified in [RFC6936] also apply.
10. IANA Considerations 10. IANA Considerations
This document does not require any IANA action. This document does not require any IANA action.
11. References 11. References
11.1. Normative References 11.1. Normative References
[RFC0768] Postel, J., "User Datagram Protocol", STD 6, RFC 768, [RFC0768] Postel, J., "User Datagram Protocol", STD 6, RFC 768,
DOI 10.17487/RFC0768, August 1980, DOI 10.17487/RFC0768, August 1980,
<https://www.rfc-editor.org/info/rfc768>. <https://www.rfc-editor.org/info/rfc768>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8762] Mirsky, G., Jun, G., Nydell, H., and R. Foote, "Simple [RFC8762] Mirsky, G., Jun, G., Nydell, H., and R. Foote, "Simple
Two-Way Active Measurement Protocol", RFC 8762, Two-Way Active Measurement Protocol", RFC 8762,
DOI 10.17487/RFC8762, March 2020, DOI 10.17487/RFC8762, March 2020,
<https://www.rfc-editor.org/info/rfc8762>. <https://www.rfc-editor.org/info/rfc8762>.
[RFC8972] Mirsky, G., Min, X., Nydell, H., Foote, R., Masputra, A., [RFC8972] Mirsky, G., Min, X., Nydell, H., Foote, R., Masputra, A.,
and E. Ruffini, "Simple Two-Way Active Measurement and E. Ruffini, "Simple Two-Way Active Measurement
Protocol Optional Extensions", RFC 8972, Protocol Optional Extensions", RFC 8972,
DOI 10.17487/RFC8972, January 2021, DOI 10.17487/RFC8972, January 2021,
<https://www.rfc-editor.org/info/rfc8972>. <https://www.rfc-editor.org/info/rfc8972>.
[I-D.gandhi-ippm-stamp-srpm] [I-D.ietf-ippm-stamp-srpm]
Gandhi, R., Filsfils, C., Voyer, D., Chen, M., and B. Gandhi, R., Filsfils, C., Voyer, D., Chen, M., Janssens,
Janssens, "Simple TWAMP (STAMP) Extensions for Segment B., and R. Foote, "Simple TWAMP (STAMP) Extensions for
Routing Networks", draft-gandhi-ippm-stamp-srpm-03 (work Segment Routing Networks", draft-ietf-ippm-stamp-srpm-00
in progress), April 2021. (work in progress), June 2021.
11.2. Informative References 11.2. Informative References
[IEEE1588] [IEEE1588]
IEEE, "1588-2008 IEEE Standard for a Precision Clock IEEE, "1588-2008 IEEE Standard for a Precision Clock
Synchronization Protocol for Networked Measurement and Synchronization Protocol for Networked Measurement and
Control Systems", March 2008. Control Systems", March 2008.
[RFC2113] Katz, D., "IP Router Alert Option", RFC 2113, [RFC2113] Katz, D., "IP Router Alert Option", RFC 2113,
DOI 10.17487/RFC2113, February 1997, DOI 10.17487/RFC2113, February 1997,
<https://www.rfc-editor.org/info/rfc2113>. <https://www.rfc-editor.org/info/rfc2113>.
[RFC4291] Hinden, R. and S. Deering, "IP Version 6 Addressing [RFC4291] Hinden, R. and S. Deering, "IP Version 6 Addressing
Architecture", RFC 4291, DOI 10.17487/RFC4291, February Architecture", RFC 4291, DOI 10.17487/RFC4291, February
2006, <https://www.rfc-editor.org/info/rfc4291>. 2006, <https://www.rfc-editor.org/info/rfc4291>.
[RFC5082] Gill, V., Heasley, J., Meyer, D., Savola, P., Ed., and C.
Pignataro, "The Generalized TTL Security Mechanism
(GTSM)", RFC 5082, DOI 10.17487/RFC5082, October 2007,
<https://www.rfc-editor.org/info/rfc5082>.
[RFC5884] Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow, [RFC5884] Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow,
"Bidirectional Forwarding Detection (BFD) for MPLS Label "Bidirectional Forwarding Detection (BFD) for MPLS Label
Switched Paths (LSPs)", RFC 5884, DOI 10.17487/RFC5884, Switched Paths (LSPs)", RFC 5884, DOI 10.17487/RFC5884,
June 2010, <https://www.rfc-editor.org/info/rfc5884>. June 2010, <https://www.rfc-editor.org/info/rfc5884>.
[RFC6437] Amante, S., Carpenter, B., Jiang, S., and J. Rajahalme, [RFC6437] Amante, S., Carpenter, B., Jiang, S., and J. Rajahalme,
"IPv6 Flow Label Specification", RFC 6437, "IPv6 Flow Label Specification", RFC 6437,
DOI 10.17487/RFC6437, November 2011, DOI 10.17487/RFC6437, November 2011,
<https://www.rfc-editor.org/info/rfc6437>. <https://www.rfc-editor.org/info/rfc6437>.
[RFC6790] Kompella, K., Drake, J., Amante, S., Henderickx, W., and
L. Yong, "The Use of Entropy Labels in MPLS Forwarding",
RFC 6790, DOI 10.17487/RFC6790, November 2012,
<https://www.rfc-editor.org/info/rfc6790>.
[RFC6936] Fairhurst, G. and M. Westerlund, "Applicability Statement [RFC6936] Fairhurst, G. and M. Westerlund, "Applicability Statement
for the Use of IPv6 UDP Datagrams with Zero Checksums", for the Use of IPv6 UDP Datagrams with Zero Checksums",
RFC 6936, DOI 10.17487/RFC6936, April 2013, RFC 6936, DOI 10.17487/RFC6936, April 2013,
<https://www.rfc-editor.org/info/rfc6936>. <https://www.rfc-editor.org/info/rfc6936>.
[RFC7404] Behringer, M. and E. Vyncke, "Using Only Link-Local [RFC7404] Behringer, M. and E. Vyncke, "Using Only Link-Local
Addressing inside an IPv6 Network", RFC 7404, Addressing inside an IPv6 Network", RFC 7404,
DOI 10.17487/RFC7404, November 2014, DOI 10.17487/RFC7404, November 2014,
<https://www.rfc-editor.org/info/rfc7404>. <https://www.rfc-editor.org/info/rfc7404>.
skipping to change at page 21, line 14 skipping to change at page 21, line 34
[RFC8986] Filsfils, C., Ed., Camarillo, P., Ed., Leddy, J., Voyer, [RFC8986] Filsfils, C., Ed., Camarillo, P., Ed., Leddy, J., Voyer,
D., Matsushima, S., and Z. Li, "Segment Routing over IPv6 D., Matsushima, S., and Z. Li, "Segment Routing over IPv6
(SRv6) Network Programming", RFC 8986, (SRv6) Network Programming", RFC 8986,
DOI 10.17487/RFC8986, February 2021, DOI 10.17487/RFC8986, February 2021,
<https://www.rfc-editor.org/info/rfc8986>. <https://www.rfc-editor.org/info/rfc8986>.
[I-D.ietf-spring-segment-routing-policy] [I-D.ietf-spring-segment-routing-policy]
Filsfils, C., Talaulikar, K., Voyer, D., Bogdanov, A., and Filsfils, C., Talaulikar, K., Voyer, D., Bogdanov, A., and
P. Mattes, "Segment Routing Policy Architecture", draft- P. Mattes, "Segment Routing Policy Architecture", draft-
ietf-spring-segment-routing-policy-09 (work in progress), ietf-spring-segment-routing-policy-11 (work in progress),
November 2020. April 2021.
[I-D.ietf-spring-sr-replication-segment] [I-D.ietf-spring-sr-replication-segment]
Voyer, D., Filsfils, C., Parekh, R., Bidgoli, H., and Z. Voyer, D., Filsfils, C., Parekh, R., Bidgoli, H., and Z.
Zhang, "SR Replication Segment for Multi-point Service Zhang, "SR Replication Segment for Multi-point Service
Delivery", draft-ietf-spring-sr-replication-segment-04 Delivery", draft-ietf-spring-sr-replication-segment-04
(work in progress), February 2021. (work in progress), February 2021.
[I-D.ietf-pim-sr-p2mp-policy] [I-D.ietf-pim-sr-p2mp-policy]
Voyer, D., Filsfils, C., Parekh, R., Bidgoli, H., and Z. Voyer, D., Filsfils, C., Parekh, R., Bidgoli, H., and Z.
Zhang, "Segment Routing Point-to-Multipoint Policy", Zhang, "Segment Routing Point-to-Multipoint Policy",
skipping to change at page 21, line 49 skipping to change at page 22, line 25
November 2020. November 2020.
[I-D.ietf-pce-sr-bidir-path] [I-D.ietf-pce-sr-bidir-path]
Li, C., Chen, M., Cheng, W., Gandhi, R., and Q. Xiong, Li, C., Chen, M., Cheng, W., Gandhi, R., and Q. Xiong,
"Path Computation Element Communication Protocol (PCEP) "Path Computation Element Communication Protocol (PCEP)
Extensions for Associated Bidirectional Segment Routing Extensions for Associated Bidirectional Segment Routing
(SR) Paths", draft-ietf-pce-sr-bidir-path-05 (work in (SR) Paths", draft-ietf-pce-sr-bidir-path-05 (work in
progress), January 2021. progress), January 2021.
[I-D.ietf-ippm-stamp-yang] [I-D.ietf-ippm-stamp-yang]
Mirsky, G., Min, X., and W. Luo, "Simple Two-way Active Mirsky, G., Min, X., and W. S. Luo, "Simple Two-way Active
Measurement Protocol (STAMP) Data Model", draft-ietf-ippm- Measurement Protocol (STAMP) Data Model", draft-ietf-ippm-
stamp-yang-07 (work in progress), March 2021. stamp-yang-07 (work in progress), March 2021.
[IEEE802.1AX] [IEEE802.1AX]
IEEE Std. 802.1AX, "IEEE Standard for Local and IEEE Std. 802.1AX, "IEEE Standard for Local and
metropolitan area networks - Link Aggregation", November metropolitan area networks - Link Aggregation", November
2008. 2008.
Acknowledgments Acknowledgments
The authors would like to thank Thierry Couture for the discussions The authors would like to thank Thierry Couture for the discussions
on the use-cases for Performance Measurement in segment routing. The on the use-cases for Performance Measurement in Segment Routing. The
authors would also like to thank Greg Mirsky, Gyan Mishra, Xie authors would also like to thank Greg Mirsky, Gyan Mishra, Xie
Jingrong, and Mike Koldychev for reviewing this document and Jingrong, and Mike Koldychev for reviewing this document and
providing useful comments and suggestions. Patrick Khordoc and Radu providing useful comments and suggestions. Patrick Khordoc and Radu
Valceanu have helped improve the mechanisms described in this Valceanu have helped improve the mechanisms described in this
document. document.
Authors' Addresses Authors' Addresses
Rakesh Gandhi (editor) Rakesh Gandhi (editor)
Cisco Systems, Inc. Cisco Systems, Inc.
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